tomney



No. 6l9,448. Patented Feb. l4, I899.

J. TOMNEY.

ELECTRIC BURGLAR ALARM.

(Application filed Oct. 471897.) v (No Model.) 2 Shaata-8hhet l.

lNV TOR BYgzm H 5 ATTORNEY Patented Feb. 14, I899.

No. 6l9,448.

(Application filed Oct. 4, 1897.)

2 Sheets-Shy? 2.

(No Model.)

HIS ATTORNEY 4% my J. m g k Q g lo? p :E: hm vvhmwpw mm UNITED STATES PATENT OFFICE.

JAMES TOMNEY, OF NEW YORK, N. Y.

ELECTRIC BU RG LAR-ALARM.

SPECIFICATION forming part of Letters Patent No. 619,448, dated February 14, 1899.

Application filed October 4,1897- To aZZ whom it may concern:

Be it known that 1, JAMES .TOMNEY, of the city, county, andStale of New York, have invented a new and useful Improvement in Electric Burglar-Alarms, of which the following is a specification.

The present invention relates to electric burglar-alarm systems, and has for its object the thorough protection of the guarded structures from a central office or station where watchmen are in attendance to respond to alarms, or, in the case of an isolated plant, any suitable indicating-point where the alarm apparatus is located.

The invention consists in the use of two or more main circuits normally closed extending from the central office or indicating-point to and through the premises to be protected. In the premises to be protected'are located devices for opening and closing the circuits, resistance coils, and electromechanical or time apparatus capable of varying the resistance and changing the path of the circuit between the guarded structure and the central office, as hereinafter described. Preferably I use an electromechanical apparatus, as that is always under the control of the operator at the engaging point and changes in the resistance and path of the circuit may be made at will. At the central office or indicatingpoint there is included in the main circuit a galvanometer or other suitable electric apparatus capable of indicating changes in the condition of the circuit, as also batteries and switches for operating and controlling the same and the instruments located at the guarded structure. When it is desired to leave the guarded structure protected only by the apparatus, the subscriber closes up the parts that are protected and signals the central office or indicating-point by means of a call-key. The alarm apparatus in the central station is then set by means of a suitable switch, and the premises are then under the care of the central office, the point from which the protecting instruments are controlled.

In the drawings I have illustrated a construction embodying my invention, in which- Figure 1 is a plan view of the instrument. Fig. 2 is a side elevation. Fig. 3 is a detail view in central section of the commutators Serial No. 653,910. (No model.)

and the connections thereto, and Fig. 4 is a diagrammatic view of the system.

Referring to Figs. 1, 2, and 3, 1 designates the base of the instrument, upon which are clamped by a clamping-plate 2 the electromagnets 3. 4 designates standards, intermediate of which is an armature 5,'pivoted on a shaft 6. This armature is provided with a tailpiece 7, which is secured to a screw 8, by means of which adjustment of the tension of the tailpiece is regulated. Also journaled between the standards 4 upon a shaft 9 is an armature 10, provided with a counterbalance 11.. This armature is also provided with a contact-point 12, which on the movement of the armature toward the electromagnets comes in contact with a contact-piece 13, secured to post 14. Mounted upon the metallic post 15 is a metallic sleeve 15, and on this sleeve are blocks of insulation 16 which carry the circuit-changer 16 and commutator 17. Within this sleeve 15 is a shaft 18, of insulated material and capable of rotation. The shaft carries at one end a ratchet 19 and a brush 20, bearing upon the sections of the circuit-changer 16, and at its opposite end a brush 21, which bears upon the sections of the commutator 17, said brush being in electrical connection with the sleeve 15 A pawl 22 is secured to the armature 5 and engages the ratchet 19, a bent arm 23 extending over the pawl 22, so as to limit its movement. The movement of the armature 10 is limited by a screw 24, projecting through a bent arm 25, secured to one of the standards 4. A brush 25 bears upon an extended portion 26 of the shaft 18, making electrical connection therewith from the end of the circuit coming out of the guarded structure.

Referring to Fig. 4E, 27 designates a galvanometer, the deflections of the needle of which are indicated by suitable alarm devices, as is usual in such constructions. 28 designates a low-potential battery, one pole of which is in connection with the galvanometer by means of a line 29, the other pole having two connections-one, 30, with the binding-post 31 of the instrument, and the other, 32, to

ground. A switch 33 is located at the central office and is connected with the galvanometer by a line 34 and is adapted to complete the circuit through the guarded structure and resistance instrument by means of line 35. A high-potential battery 36 is connected to the switch 33 and has two conuectionsone, 37, to ground, and the other, 38, with the line 30. 39 designates a key for opening the circuit from the guarded structure with the central otfice. 4O designates the guarded structure.

The method of operation is as follows: The circuit being closed, the low-potential battery in circuit, and the high-potential battery out of circuit, (which position is shown in Fig. 4,) the electric circuit will be from the battery 28 to the galvanometer, through the galvanometer to the switch 33, through the switch 33 along line 35, through the guarded structure 40 to binding-post 41, through the electromagnets of the instrument along the wire 42, through the post 15 and sleeve 15 to the commutator-brush 21, through the section of the commutator upon which the brush bears along wire 43, connecting the section with the resistance-coil 44. The path of the current is then from the resistance-coil along line to binding-post 46, thence along line 47 through the guarded structure to binding-post 48, from which binding-post the current passes along line 49, through the brush 25 to the commutator-brush 20, which bears upon a section of the circuit-changer 16, through the section of said circuit-changer along line 50 to binding-post 51, and thence to ground. This circuit will indicate a given resistance,which the operator at the central office knows.

It will be understood that the several sections of the commutators are connected with difierent resistances, as is indicated in the drawings. When the operator at the central office desires to throw in circuit another resistance, he momentarily switches in the high-potential battery 36, thus cutting out the galvanometer. During this momentary inclusion of the high-potential battery the circuit is initially for an instant the same as has been just described; but the effect of the high-potential battery is to so energize the electromagnets that the counterbalanced armature 10, which requires little force to operate it,is attracted, so that the arm 12 makes contact with the contactpoint 13 on post 14. This establishes a short circuit through the electromagnets, throwing out the commutator resistance-coils, a circuitchanger establishing a direct return, the path of the current being then from the bindingpost 41 through the coils along line 42, then through line 52 to the armature 10, through post 14, from the post 14 along line 53 to bind ing-post 31, and from thence along line 54 to the other poles of the high-potential battery. By so cutting out the resistances the power of the electromagnets is greatly increased, so that they attract the armature 4, to which is connected the pawl 22, which by its connections with the ratchet 19 turns the shaft 18, so as to bring both the brushes 20 and 21 to bear upon the next section of their respective circuit-changer 16 and commutator 17. The

high-potential battery is then cut out and the low-potential battery thrown in circuit, the path of the circuit then being from the low potential battery through the galvanometer, through the switch 33 along line 35, through the guarded structure to binding-post 41, through the electromagnets to the brush 21, through the section 55 of commutator 17 along line 56, through a portion of the resistance-coil 44, from the resistance-coil back to binding-post 46, then returned through the guarded structure to binding-post 48, thence to brush 20 to section 57 of circuitchanger 16, through line 58 to binding-post 31, then along return-wire 54 to the other pole of the low -potential battery. These three illustrations will suffice to indicate the operation of the instrument. It will be noted that the first circuit was through a given resistance back to the source of electricity through ground. Then the high-potential battery was thrown in, the brushes of the commutators moved so as to communicate with another resistance, then the high-potential battery was cut out and the low-potential battery thrown in circuit again, the path then being through the new sections of the commutator and a different portion of the resistance-coils, and through line instead of through ground, as in the first instance.

It of course will be understood that instead of a centraloffice from which a number of guarded structures are cared for an indicating-point in the case of an isolated plant would be the equivalent of a central oifice. Also instead of the electromechanical apparatus here described a suitable mechanism controlled by clockwork, which will operate to bring in the changes in resistance and in the return-circuit at predetermined periods, would also come under the scope of the present invention so long as such mechanism effected a change in the resistance and a change in the path of the circuit.

What is claimedas new is p 1. In an electric protective system, the combination of a plurality of electrical connections forming a plurality of circuits between an indicating-point and a guarded structure, a number of variable resistances located in said connections, and means for changing such resistances and the path of the circuit between the guarded structure and the indicating-point, substantially as described.

2. In an electric protective system, the combination of a plurality of electrical connections forming a plurality of circuits between an indicating-point and a guarded structure, a number of variable resistances located in said connections, and means for changing at will such resistances and the path of the circuit between the guarded structure and the indicating-point, substantially as described.

3. In an electric protective system, the combination of an indicating-point and a guarded structure,of a conductor from said indicatingpoint to said guarded structure forming a single circuit-path, of a multiplicity of conductors from said guarded structure to said indicating-point forming a multiplicity of return circuit-paths, variable resistances located in said paths and means for changing said resistances and the return-path for the circuit, substantially as described.

4. The combination of an electromagnet, a movable armature for said magnet, a comm utator and variable resistances connected to the sections of the commutator, a circuitchanger, a connection between the commutator, circuit-changer and the armature, and means for simultaneously effecting changes in the path of the circuit and the Variable re sistances, substantially as specified.

5. The combination of an electromagnet, a movable armature therefor, a short-circuiting armature also for said magnet for cutting out resistances to permit the first armature to act, a commutator having variable resistances, a circuit-changer, a connection between the commutator, circuit-changer and the first armature, whereby movements of the first armature will effect simultaneous changes in the path of the circuit and the variable resistances, substantially as specified.

6. The combination of an electromagnet, a movable armature, a short-circuiting armature, a commutator having variable resistances, a rotating brush traveling over the commutator, a circuit changer, a ratchet mounted to turn with the brush, and a pawl secured to the movable armature and adapted to engage the ratchet whereby the movements of the armature will cause the rotation of the brush and efiect changes in the path of the circuit and the variable resistances, substantially as specified.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

- JAMES TOMNEY. Witnesses:

ERNEST HOPKINSON, W. LAIRD GOLDSBOROUGH. 

